﻿using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Web;

namespace Achievement.Common
{
    public class SqlKey
    {

        private HttpRequest request;

        private const string StrKeyWord = @"select|insert|delete|from|count(|drop table|update|truncate|asc(|mid(|char(|xp_cmdshell|exec master|netlocalgroup administrators|:|net user|""|or|and";

        private const string StrRegex = @"-|;|/|(|)|[|]|}|{|%|@|*|!|'";

        public SqlKey(System.Web.HttpRequest _request)
        {

            //

            // TODO: 在此处添加构造函数逻辑

            //

            this.request = _request;

        }



        /**/
        /// <summary>

        /// 只读属性 SQL关键字

        /// </summary>

        public static string KeyWord
        {

            get
            {

                return StrKeyWord;

            }

        }

        /**/
        /// <summary>

        /// 只读属性过滤特殊字符

        /// </summary>

        public static string RegexString
        {

            get
            {

                return StrRegex;

            }

        }

        /**/
        /// <summary>

        /// 检查URL参数中是否带有SQL注入可能关键字。

        /// </summary>

        /// <param name="_request">当前HttpRequest对象</param>

        /// <returns>存在SQL注入关键字true存在，false不存在</returns>

        public bool CheckRequestQuery()
        {

            if (request.QueryString.Count != 0)
            {

                //若URL中参数存在，逐个比较参数。

                foreach (string i in this.request.QueryString)
                {

                    // 检查参数值是否合法。

                    if (i == "__VIEWSTATE") continue;

                    if (i == "__EVENTVALIDATION") continue;

                    if (CheckKeyWord(request.QueryString[i].ToString()))
                    {
                        //request.QueryString[i] = null;
                        return true;

                    }

                }

            }

            return false;

        }



        /**/
        /// <summary>

        /// 检查提交表单中是否存在SQL注入可能关键字

        /// </summary>

        /// <param name="_request">当前HttpRequest对象</param>

        /// <returns>存在SQL注入关键字true存在，false不存在</returns>

        public bool CheckRequestForm()
        {

            if (request.Form.Count > 0)
            {



                //获取提交的表单项不为0 逐个比较参数

                foreach (string i in this.request.Form)
                {

                    if (i == "__VIEWSTATE") continue;

                    if (i == "__EVENTVALIDATION") continue;

                    //检查参数值是否合法

                    if (CheckKeyWord(request.Form[i]))
                    {

                        //存在SQL关键字
                        //request.Form[i] = null;
                        return true;



                    }

                }

            }

            return false;

        }



        /**/
        /// <summary>

        /// 静态方法，检查_sword是否包涵SQL关键字

        /// </summary>

        /// <param name="_sWord">被检查的字符串</param>

        /// <returns>存在SQL关键字返回true，不存在返回false</returns>

        public static bool CheckKeyWord(string _sWord)
        {

            string word = _sWord;

            string[] patten1 = StrKeyWord.Split('|');

            string[] patten2 = StrRegex.Split('|');

            foreach (string i in patten1)
            {

                if (word.Contains(" " + i) || word.Contains(i + " "))
                {

                    return true;

                }

            }

            foreach (string i in patten2)
            {

                if (word.Contains(i))
                {

                    return true;

                }

            }

            return false;

        }



        /**/
        /// <summary>

        /// 反SQL注入:返回1无注入信息，否则返回错误处理

        /// </summary>

        /// <returns>返回1无注入信息，否则返回错误处理</returns>

        public string CheckMessage()
        {

            string msg = "1";

            if (CheckRequestQuery()) //CheckRequestQuery() || CheckRequestForm()
            {

                //msg = "<span style='font-size:24px;'>非法操作！<br>";

                //msg += "操作IP：" + request.ServerVariables["REMOTE_ADDR"] + "<br>";

                //msg += "操作时间：" + DateTime.Now + "<br>";

                //msg += "页面：" + request.ServerVariables["URL"].ToLower() + "<br>";

                //msg += "<a href="#" onclick="history.back()">返回上一页</a></span>";

            }

            return msg.ToString();

        }

    }

}
